Alkaline Phosphatase Test

An ALP test is done to check the following disorders:

• Liver disorders
• Bone disorders, such as rickets, Paget’s disease, bone tumours or an increase in the parathyroid hormone

Few signs and symptoms that indicate liver involvement are:

• Weakness
• Fatigue
• Unexplained loss of appetite
• Nausea
• Vomiting
• Abdominal swelling and pain (Read more: Abdominal pain causes)
• Jaundice (yellowing of the skin and whites of the eye)
• Dark-coloured urine
• Light-coloured stool
• Itching (pruritus)

Signs and symptoms that indicate bone involvement are:

• Bone pain and joint pain
• Deformation in bones
• Increase in the frequency of fractures

ALP test can also be performed in some other condition. These include:    

• Alcoholic liver disease such as hepatitis/cirrhosis
• Alcoholism
• Biliary stricture (abnormal narrowing of the bile duct)
• Gallstones
• Giant cell (temporal, cranial) arteritis (a disease of blood vessels)
• Multiple endocrine neoplasia (MEN) II (a disorder in which endocrine glands become overactive and form a tumour)
• Pancreatitis
• Renal cell carcinoma (a type of kidney cancer)

Do not eat or drink anything for about 10 hours prior to the test as ALP levels can increase after eating fatty foods.

Inform your doctor if you are on any medication or supplements. He/she can advise you to stop certain medicines that can alter test results. Antibiotics narcotics, methyldopa, propranolol, cortisone, allopurinol, tricyclic antidepressants, androgens, tranquilisers, chlorpromazine, oral contraceptives (birth control pills), anti-inflammatory analgesics, antiarthritic drugs and oral antidiabetic drugs are few drugs that could affect ALP levels.

It is a simple procedure in which a blood sample will be withdrawn from a vein in your arm after swabbing the concerned area with an antiseptic solution.

After collection of the sample, the injection site will be pressed firmly, and a cotton ball or gauze pad will be placed over that area to stop bleeding. The collected blood sample will be further sent for examination.

Results of an ALP test can vary depending upon the method used and the age, gender, and health history of the individual. It is best to check in with a doctor to get the correct interpretation of results.

Normal results: The normal range of ALP for men and women older than 18 years is 37-116 units per litre (U/L).

Normal ranges for children and teenagers are:

• For boys    
  • 1-3 years: 104-345 U/L
  • 4-6 years: 93-309 U/L
  • 7-9 years: 86-315 U/L
  • 10-12 years: 42-362 U/L
  • 13-15 years: 74-390 U/L
  • 16-18 years: 52-171 U/L
• For girls    
  • 1-3 years: 108-317 U/L
  • 4-6 years: 96-297 U/L
  • 7-9 years: 69-325 U/L
  • 10-12 years: 51-332 U/L
  • 13-15 years: 50-162 U/L
  • 16-18 years: 47-119 U/L

Abnormal results: Higher levels of ALP can be seen in the following conditions:

• Biliary obstruction (blockage of bile ducts)
• Bone diseases or disorders
• Osteoblastic bone cancers/tumours
• Osteomalacia (softening of bones)
• Healing fractures
• Liver disease
• Hepatitis
• Hyperparathyroidism (over secretion of parathyroid hormone)
• Leukaemia (cancer in blood-forming tissues)
• Lymphoma (cancer in lymphocytes)
• Paget’s disease
• Rickets
• Sarcoidosis (formation of granulomas in the body)
• Anaemia

Lower levels of ALP can be seen in the following conditions:

• Malnutrition
• Protein deficiency
• Hypophosphatasia
• Wilson disease

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. The above information is provided from a purely educational point of view and is in no way a substitute for medical advice by a qualified doctor.